Messages in this thread | | | Date | Thu, 09 Jul 2015 09:28:30 +0800 | From | Pan Xinhui <> | Subject | Re: [PATCH V2] acpi-cpufreq: replace per_cpu with driver_data of policy |
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hi, Rafael thanks for your kind reply. :)
On 2015年07月09日 08:20, Rafael J. Wysocki wrote: > On Tuesday, July 07, 2015 08:04:43 PM Viresh Kumar wrote: >> On 07-07-15, 20:43, Pan Xinhui wrote: >>> >>> Drivers can store their internal per-policy information in >>> policy->driver_data, lets use it. >>> >>> we have benefits after this replacing. >>> 1) memory saving. >>> 2) policy is shared by several cpus, per_cpu seems not correct. using >>> *driver_data* is more reasonable. >>> 3) fix a memory leak in acpi_cpufreq_cpu_exit. as policy->cpu might >>> change during cpu hotplug. So sometimes we cant't free *data*, use >>> *driver_data* to fix it. >>> 4) fix a zero return value of get_cur_freq_on_cpu. Only per_cpu of >>> policy->cpu is set to *data*, if we try to get cpufreq on other cpus, we >>> get zero instead of correct values. Use *driver_data* to fix it. >>> >>> Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com> >>> --- >>> Changes from V1: >>> codes style fix, comments update >>> move cpufreq_cpu_put(policy) after we get *driver_data* >>> --- >>> drivers/cpufreq/acpi-cpufreq.c | 40 ++++++++++++++++++++++------------------ >>> 1 file changed, 22 insertions(+), 18 deletions(-) >> >> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> > > OK > > Does it fix any recent regressions or is it just an old bug? >
This patch achieve old bug fix and codes improvements. In past days, policy has no field *driver_data*, So acpi-cpufreq driver has to use per_cpu to store some extra information. But it did not take good care of every scenarios. Now cpufreq core makes awesome effort to store more per-policy information in policy. We can make use of this feature. So I cook this patch. :)
I am preparing two patches for other two issues in acpi-cpufreq driver based on this patch. I will fix them step by step. :)
thanks xinhui
> Rafael >
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